KYIV, Ukraine, Aug 20, 2023 (BSS/AFP) - Ukrainian President Volodymyr Zelensky arrived in the Netherlands on Sunday aiming to strengthen his country's air power, a day after a "heinous" Russian missile strike killed seven people and wounded 148 in Chernihiv.

The United States on Friday approved the transfer to Ukraine of Dutch and Danish US-made F-16 fighter jets, a key demand by Kyiv as it seeks greater firepower from allies during a grinding counteroffensive against Russia.

Zelensky's flight landed at a Dutch air force base in Eindhoven at around midday (1000 GMT), a Dutch government spokesperson told AFP, although details of the delivery of aircraft to Ukraine have not been unveiled.

"Together with the First Lady and the team, we arrived in the Netherlands. As always, we will have substantive talks with Prime Minister Mark Rutte," Zelensky posted on Telegram in English.

"The main issue is F-16 for Ukraine to protect our people from Russian terror. We are getting stronger."

The Netherlands and Denmark are leading a plan to train Ukrainian pilots on using the US-made aircraft as part of an 11-nation coalition, with training potentially complete by early 2024.

Washington has strict rules on the sale or transfer of US military equipment by its allies.

Russian Foreign Minister Sergei Lavrov has said Moscow will regard Western F-16 fighter jets sent to Ukraine as a "nuclear" threat because of their capacity to carry atomic weapons.

Zelensky was in Sweden on Saturday, finalising with Prime Minister Ulf Kristersson the production of CV90 armoured vehicles in Ukraine and Ukrainian pilots participating in test trials of Swedish Gripen fighter jets.

- Drones downed in Russia -

Russia said it thwarted Ukrainian drone attacks on Moscow and its region on Sunday, the second such incident in two days.

Both sides have reported regular drone incursions during the conflict, with strikes on Russian territory becoming increasingly regular.

"At around 4:00 am (0100 GMT), an attempt by the Kyiv regime to carry out a terrorist attack by drone on infrastructure in Moscow and the Moscow region was thwarted," the Russian defence ministry said in a statement.

The Moscow-bound drone was destroyed by "electronic warfare" and crashed into an uninhabited area after losing control, the ministry added, reporting no victims or damage.

Moscow mayor Sergei Sobyanin thanked Russia's military for their work on the Telegram messaging app.

Aviation agency Rosaviatsia said flights to the Domodedovo and Vnukovo international airports were "temporarily limited" at night before returning to normal, according to the RIA Novosti news agency.

A Ukrainian drone raid also hit a railway station in the western Russian city of Kursk, injuring five people, the regional governor said early Sunday.

In the southern region of Rostov that borders Ukraine, Russian air defence intercepted two Ukrainian drones, the governor said.

- 'Heinous' attack in Chernihiv -

Zelensky vowed "a tangible answer" to Saturday's attack on the northern Ukrainian city of Chernihiv, which came during the Orthodox holiday of the Transfiguration of the Lord as some attended morning church services.

Vyacheslav Chaus, governor of the Chernihiv region, announced "7 people dead, 148 people received injuries" in an update on Sunday.

"41 people remain in hospitals. 15 people underwent surgeries," he said in a post on Telegram, adding that "more than 500 homes suffered damage".

Zelensky had noted the dead included a six-year-old girl and that there were 15 children among the wounded.

Denise Brown, UN humanitarian coordinator for Ukraine, said it was "heinous to attack the main square of a large city, in the morning, while people are out walking, some going to church to celebrate a religious day for many Ukrainians".

Chernihiv, 150 kilometres (90 miles) north of Kyiv towards Belarus, had largely been spared from major attacks since the first months of Russia's invasion as fierce fighting rages in the east and south.

The Russian army marched through the city when it invaded Ukraine through Belarus in February 2022, before being repelled by Kyiv's forces.

Ukraine launched its widely expected counteroffensive in June but has come up against fierce resistance from entrenched Russian forces.